Forty-three Republican senators protected Donald Trump from accountability for inciting the insurrection at the U.S. Capitol when they voted to acquit in his second impeachment trial. They’re going to have a challenge protecting him—and maybe themselves—through the likely next phase of the response to the Jan. 6 attack: an investigation by a bipartisan commission similar to the 9/11 commission. The question is how serious and how empowered such an investigation will be, and Democrats need to ensure that the answer is “very.”

House Speaker Nancy Pelosi called for such an investigation in early February, writing to House Democrats, “It is also clear that we will need to establish a 9/11-type Commission to examine and report upon the facts, causes and security relating to the terrorist mob attack on January 6.” Retired Lt. Gen. Russel Honoré is already leading a security review, but the question of protecting the U.S. Capitol as a physical building is different from understanding how Jan. 6 happened—from incitement to active planning to responses while it was underway—and not just Congress but the whole nation needs to understand that.

We need to know more about Trump’s actions. The House impeachment managers laid out his public-facing statements showing that he absolutely called his supporters to Washington, D.C., on Jan. 6 in an attempt to prevent Congress from certifying President Biden’s election win, and that he continued to encourage them even as they were breaching the Capitol. But we know there’s more. Republican Rep. Jaime Herrera Beutler has described a phone call between House Minority Leader Kevin McCarthy and Trump in the midst of the attack in which McCarthy asked Trump “to publicly and forcefully call off the riot,” only to have Trump tell him, “Well, Kevin, I guess these people are more upset about the election than you are.” McCarthy told Herrera Beutler about the call. He needs to tell investigators about it, too. 

And Herrera Beutler’s Friday statement on that call pointed out that McCarthy isn’t the only likely witness: “To the patriots who were standing next to the former president as these conversations were happening, or even to the former vice president: if you have something to add here, now would be the time,” she said. That didn’t happen in time for the impeachment trial, but those people are still out there, and a bipartisan commission with subpoena power could potentially uncover some of them, along with many other facts that are necessary for ensuring this never happens again … but potentially very inconvenient for Trump and some other Republicans.

We also need to know more about failures by the Capitol Police and others tasked with protecting the Capitol. How did they miss the signs that this wasn’t going to be a peaceful free speech rally? We need to know who at the Pentagon did what with regard to National Guard deployments ahead of Jan. 6 and as the Capitol was under attack.

Lawmakers from both parties have called for a 9/11-type investigatory panel, but some of the Republicans are likely to either push for tight limits on what can be investigated or entirely back off those calls as impeachment—and the need to distract from it by acting very serious about some form of response to the attack—recedes into the past. 

“We need a 9/11 Commission to find out what happened and make sure it never happens again, and I want to make sure that the Capitol footprint can be better defended next time,” Sen. Lindsey Graham said Sunday, but let’s wait to hear the series of things he doesn’t want included and witnesses he doesn’t want called in the investigation. The second item on Graham’s list is likely to become a big Republican talking point—refocusing the response from “what happened and how can we understand it” to “what physical fortifications do we need.” It’s the Republican way: guns, not accountability.

Republicans will also start screaming if, for instance, some of their own start getting called as witnesses. It would be very interesting to hear from Sens. Josh Hawley and Ted Cruz, for instance, or Reps. Lauren Boebert and Marjorie Taylor Greene.

But a 9/11-type commission isn’t the only investigation in the works. Graham himself could be drawn into an investigation into efforts to overturn the Georgia election. Secretary of State Brad Raffensperger recorded the phone call in which Trump pressured him to “find 11,780 votes” because of an earlier phone call in which Graham asked him to illegally reject large numbers of ballots. That Georgia investigation obviously will focus on Trump. Trump also faces the possibility of a criminal investigation into Jan. 6. That’s a very remote possibility now, but given an empowered, detailed (the 9/11 commission investigated for 20 months) look into what happened … well, we can dream.

It’s unlikely that too many people will come out fully against an investigation into the attack on the Capitol. The thing to watch is what limits Republicans want to place on it. What questions do they think should be off limits? What witnesses do they not want called? Especially from people like Graham and Cruz and Hawley, that’s going to be a signal of where the really important information is—and both Democrats and good-faith Republicans need to be willing to pursue it.

Forty-three Republican senators protected Donald Trump from accountability for inciting the insurrection at the U.S. Capitol when they voted to acquit in his second impeachment trial. They’re going to have a challenge protecting him—and maybe themselves—through the likely next phase of the response to the Jan. 6 attack: an investigation by a bipartisan commission similar to the 9/11 commission. The question is how serious and how empowered such an investigation will be, and Democrats need to ensure that the answer is “very.”

House Speaker Nancy Pelosi called for such an investigation in early February, writing to House Democrats, “It is also clear that we will need to establish a 9/11-type Commission to examine and report upon the facts, causes and security relating to the terrorist mob attack on January 6.” Retired Lt. Gen. Russel Honoré is already leading a security review, but the question of protecting the U.S. Capitol as a physical building is different from understanding how Jan. 6 happened—from incitement to active planning to responses while it was underway—and not just Congress but the whole nation needs to understand that.

We need to know more about Trump’s actions. The House impeachment managers laid out his public-facing statements showing that he absolutely called his supporters to Washington, D.C., on Jan. 6 in an attempt to prevent Congress from certifying President Biden’s election win, and that he continued to encourage them even as they were breaching the Capitol. But we know there’s more. Republican Rep. Jaime Herrera Beutler has described a phone call between House Minority Leader Kevin McCarthy and Trump in the midst of the attack in which McCarthy asked Trump “to publicly and forcefully call off the riot,” only to have Trump tell him, “Well, Kevin, I guess these people are more upset about the election than you are.” McCarthy told Herrera Beutler about the call. He needs to tell investigators about it, too. 

And Herrera Beutler’s Friday statement on that call pointed out that McCarthy isn’t the only likely witness: “To the patriots who were standing next to the former president as these conversations were happening, or even to the former vice president: if you have something to add here, now would be the time,” she said. That didn’t happen in time for the impeachment trial, but those people are still out there, and a bipartisan commission with subpoena power could potentially uncover some of them, along with many other facts that are necessary for ensuring this never happens again … but potentially very inconvenient for Trump and some other Republicans.

We also need to know more about failures by the Capitol Police and others tasked with protecting the Capitol. How did they miss the signs that this wasn’t going to be a peaceful free speech rally? We need to know who at the Pentagon did what with regard to National Guard deployments ahead of Jan. 6 and as the Capitol was under attack.

Lawmakers from both parties have called for a 9/11-type investigatory panel, but some of the Republicans are likely to either push for tight limits on what can be investigated or entirely back off those calls as impeachment—and the need to distract from it by acting very serious about some form of response to the attack—recedes into the past. 

“We need a 9/11 Commission to find out what happened and make sure it never happens again, and I want to make sure that the Capitol footprint can be better defended next time,” Sen. Lindsey Graham said Sunday, but let’s wait to hear the series of things he doesn’t want included and witnesses he doesn’t want called in the investigation. The second item on Graham’s list is likely to become a big Republican talking point—refocusing the response from “what happened and how can we understand it” to “what physical fortifications do we need.” It’s the Republican way: guns, not accountability.

Republicans will also start screaming if, for instance, some of their own start getting called as witnesses. It would be very interesting to hear from Sens. Josh Hawley and Ted Cruz, for instance, or Reps. Lauren Boebert and Marjorie Taylor Greene.

But a 9/11-type commission isn’t the only investigation in the works. Graham himself could be drawn into an investigation into efforts to overturn the Georgia election. Secretary of State Brad Raffensperger recorded the phone call in which Trump pressured him to “find 11,780 votes” because of an earlier phone call in which Graham asked him to illegally reject large numbers of ballots. That Georgia investigation obviously will focus on Trump. Trump also faces the possibility of a criminal investigation into Jan. 6. That’s a very remote possibility now, but given an empowered, detailed (the 9/11 commission investigated for 20 months) look into what happened … well, we can dream.

It’s unlikely that too many people will come out fully against an investigation into the attack on the Capitol. The thing to watch is what limits Republicans want to place on it. What questions do they think should be off limits? What witnesses do they not want called? Especially from people like Graham and Cruz and Hawley, that’s going to be a signal of where the really important information is—and both Democrats and good-faith Republicans need to be willing to pursue it.